Paint spray booth

ABSTRACT

A paint spray booth, including side and top walls, the top wall having a vent opening, means for supporting a roll of curtain material, consisting of a layer of non-woven fabric and a scrim of woven material, outside and above said booth, a portion of the said material of said roll, extending downwardly to form one wall of said booth, another portion of said material extending rearwardly and away from said first roll to a collapsible recovery shaft positioned outside of the paint spray area.

United States Patent [191 Hardy I 11] 3,811,371 1451 May 21, 1974 PAINT SPRAY BOOTH [76] Inventor: Sheila Hardy, 400 North Ave.,

Bartlett, 111. 60103 [22] Filed: May 8, 1972 [21] Appl. No.: 251,087

Related US. Application Data [62] Division of Ser. No. 75,843, Sept. 28, 1970,

abandoned.

[52] US. Cl. 98/115 SB [51] Int. Cl F23j 11/00 [58] Field of Search 98/115; 26/76 [5 6] References Cited UNITED STATES PATENTS 3,071,060 H1963 Forshee 98/115 2,875,680 3/1959 Forshee 2,841,073 7/1958 Forshee 98/115 1,982,639 12/1934 Christofferson 98/115 1/1967 Pernick 3,299,484 26/70 3,633,211 l/1972 BatzdoriT 26/70 FOREIGN PATENTS OR APPLICATIONS 1,020,591 2/1966 Great Britain 98/1 15 Primary Examiner-William F. ODea Assistant Examiner-Paul Devinsky [57] ABSTRACT A paint spray booth, including side and top walls, the top wall having a vent opening, means for supporting a roll of curtain material, consisting of a layer of nonwoven fabric and a scrim of woven material, outside and above said booth, a portion of the said material of said roll, extending downwardly to form one wall of said booth, another portion of said material extending rearwardly and away from said first roll to a collapsible recovery shaft positioned outside of the paint spray area.

6 Claims, 3 Drawing Figures PAINT SPRAY BOOTH This invention relates to paint spray booths and particularly to means for trapping paint overspray. This Application is a Division of my Co-pending application Ser. No. 75843, filed Sept. 28, l970 now abandoned, and covers improvements to the devices disclosed in U.S. Pat. No. 2,841,073-No. 2,875,680-and No. 3,071,060 issued to me under my previous name Sheila Forshee.

An object of this invention is to provide a simplified and more compact paint spray booth, whereby to effect economies in the floor space needed, reduction in parts, and cost of manufacturing and installation.

Another object of the invention is to improve paint spray booths of the character indicated, whereby its possible to trap not only the conventional type of paint, but to trap the overspray of the modern day sophisticated coating products, now used in industry.

Another object of the invention is to provide improved means for trapping paint overspray, which perrnits the paint laden portions of the curtain material to be wound tightly about a collapsible member, in which condition it readily may be disposed of, thereby obviating an possibility of aeriating and oxidizing the curtain material and causing spontaneous combustion.

Another object of the invention is to provide an improved, flame proof, curtain material which meets all of the safety requirements of the Underwriters Laboratory, and National Fire Protection Association.

Another object of the invention is to provide an improved curtain material, which preverits any emission of paint particles to atmosphere, thereby improving the ecology by the elimination of air pollutants] Another object of the invention is to provide a device of the character indicated with an upwardly canted panel, enabling the curtain to better control the flow of air.

Another object of the invention is to provide ventilation for the curtain wall completely to the floor and to provide a greater exposed trapping area.

Another object of the invention is to obviate the possibility of accumulating paint residue on certain parts of the device.

Another object of the invention is to locate thefresh supply of cu rtain material well above and outside of the working area. Thisfacilitates the loading of the roll and obviates the possibility of any paint residue damaging the roll and enables an operator, or an inspector, to visualize the unused portion of the roll during any time of a continuous spraying operation.

Another object of the invention is to provide a device of the character indicated, in which the curtain mate rial is fed downwardly and reversely under a roller and up over an idler to provide a natural break for the curtain, thereby obviating the possibility of the curtain billowing, in the event of a negative plant pressure or back draft. This insures the proper performance and functioning ofthe device, regardless of air-conditioning in the plant.

Another object of the invention is to provide improved means at the rear of the device for collecting and more readily disposing of the paint saturated portions of the curtain material. This improves the fire and safety factors of the device and permits the used curtain material to be readily unloaded from outside the working area. It also enables the operator or inspector to visually determine, without any work stoppage, when to unload the device, thereby avoiding serious overloading.

The foregoing and other objects and advantages of the invention will become more apparent as the description proceeds, reference being made from time to time to the accompanying drawing: 1

FIG. 1 is a side elevational view of a device embodying the invention, with parts broken away and parts in section.

FIG. 2 is a front perspective view of the device shown in FIG. 1.

FIG. 3 is a rear perspective view of the device shown in FIG. 2, withparts broken away and parts in section.

Referring now more particularly to the drawings, it will be understood that in the embodiment herein disclosed, the reference character 7, indicated, in general, a working canopy 7 in which an operator 8 uses a paint spray device 9, as previously described in U.S. Pat. No. 2,875,680. The canopy 7 consists of a pair of lateral members 10 and 11, which support the top panel 12, which is preferably made of metal and a plurality of vertical members 13 and. 14, which support the outboard ends of the side panels 15 and 16, which are also preferably made of metal. The inboard edges of the panels 15 and 16 are supported by angle members 17 and 18 (FIG. 2), which form a frame work for the end of the canopy 7. The lower ends of the side panels 15 and 16 rest upon strap members 19, which may be secured to the floor as at 20 (FIG. 2). The upper front edge of the canopy 7 is provided with an air shield 21, which is adapted to prevent the forced air from escaping from the upper front portion of the canopy.

The elements just described form no part of the invention, except as they are combined with the elements hereinafter described.

The elements embodying the improvements which are intended to be covered by the within application will now be described.

A frame work, comprising elements 25 through 33, which are made of an angle iron, or other suitable material, are welded, or otherwise secured together, as shown in FIG. 3, supports and houses the other elements comprising the invention device. The frame work supports the side panel members 34 and 35, the front panel 'member 36 and a top panel member 37. The combined elements just described also serve as a conduit for the air forced through the'device, which air is exhausted through the opening 38, in the top panel 37, and into the exhaust stack 39 (FIG. I), in which is installed a suitable exhaust pump, or fan 40.

Rotatably mounted on extensions of the frame members 30 and, 31 as at 41, is .a roll of fabric material 42, which consists of .a layer of nonwoven fabric and a scrim of woven fabric. The fabric material 42 is more particularly described and claimed in my Co-pending application, Ser. No. 75845, filed Sept. 28, 1970, now U.S. Pat. No. 3,727,147.

A portion of the fabric of the roll 42 extends downwardly as at 43, and under a roller 44 and then upwardly over an idler roller 45 and thence downwardly as at 46, and beneath a roller 47, from which it extends as at 48 to a collection area 52, where it is picked up and wound around a' collapsible shaft 49, the latter being pivoted in suitable bearings 51 (FIG. 3), which are carried by suitable supports, which are mounted at 3 either end of the shaft in the collection compartment 52, the latter being closed at the top by means of a removable cover 53. The collapsible shaft 49 is rotated at desired periods by means of a motor 54 and a reduction gear 55. An optional hand crank may also be used to rotate the shaft 49. The collapsible shaft 49 is more specifically described and claimed in my Co-pending application, Ser. No. 75844, filed Sept. 28, i970, now US. Pat. No. 3,729,147.

The motor 54 is connected to a suitable control member 56 through the lead 57, and is arranged to .index thedevice for a fresh section of curtain material and the removal of the paint laden portion of the fabric curtain.

It will be understood that the portion 46 of the fabric material just described forms the front wall of the structure 30-37. It will also be understood that the portion 46 of the fabric is backed up and reinforced by means of a heavy screen or grid of steel tubing 58, so that the air may be forced through and around the fabric portion 46, as previously disclosed in US. Pat. No.

I 2,875,680 and as indicated hereinabove. In order to enhance the flow of air through the fabric 46 and the grid or screen 58, I provide an angularly positioned baffle 60, which extends from the top panel 37 to a point immediately above the fabric portion 48 and slightly ahead of the position of the collapsible shaft 49.

The positioning of the fabric roll 42 above and out of the spray canopy 7 enables the device to be replenished with a new roll of fabric entirely from the exterior of the device, and without danger of having it contaminated during a spraying cycle.

The positioning of the collapsible-shaft 49 in its own compartment 52, at the rear of the device, makes it readily accessible from the outside rear of the structure, achieves greater safety, increases the protection of the operator, achieves an uninterrupted process cycle. Y

The passing of the fabric under and over the rolls 44 and 45 provides a natural break for the operating .curtain 46, thereby eliminating the possible billowing of the curtain, due to a negative plant pressure, or

It is believed that the operation of the device is obvious from the foregoing description. I

Having described my invention, what I claim and desire to secure by Letters Patent is:

l. in a paint spray booth consisting of side walls and a top wall, said side and top walls having front extensions forming a canopy, the improvements consisting of a pair of storage roll supports positioned above said top wall and extending beyond said side walls and overlying a portion of said canopy, a roll of non-woven fabric material on said supports, said roll of material having a portion extending between a pair of upper rollers and thence downwardly over a lower roller to form a front wall, which is of substantially the same height as said side walls, said pair of upper rollers forming a natural break for said front wall, whereby to obviate any possibility of the front wall billowing when a back draft or negative air pressure exists during shutdown.

2. The structure of claim 1, including a friction free back stop for said front wall portion of said material, consisting of a plurality 'of spaced, laterally directed tubes.

3. The structure of claim 1, in which there is an angularly directed baffle spaced from said front wall and coextensive therewith, and forming the back wall of said booth, a portion of said curtain material extending under the lower end of said baffle, whereby to provide effective filtering and air movement from the floor to I theair exhaust stack.

4. The structure of claim 1,,in which said canopy is provided with an angular air shield at the top of its open end.

back-draft, all of which improve the practice of my method.

5. The structure of claim 3, in which the portion of -ric material, 

1. In a paint spray booth consisting of side walls and a top wall, said side and top walls having front extensions forming a canopy, the improvements consisting of a pair of storage roll supports positioned above said top wall and extending beyond said side walls and overlying a portion of said canopy, a roll of nonwoven fabric material on said supports, said roll of material having a portion extending between a pair of upper rollers and thence downwardly over a lower roller to form a front wall, which is of substantially the same height as said side walls, said pair of upper rollers forming a natural ''''break'''' for said front wall, whereby to obviate any possibility of the front wall billowing when a back draft or negative air pressure exists during shutdown.
 2. The structure of claim 1, including a friction free back stop for said front wall portion of said material, consisting of a plurality of spaced, laterally directed tubes.
 3. The structure of claim 1, in which there is an angularly directed baffle spaced from said front wall and coextensive therewith, and forming the back wall of said booth, a portion of said curtain material extending under the lower end of said baffle, whereby to provide effective filtering and air movement from the floor to the air exhaust stack.
 4. The structure of claim 1, in which said canopy is provided with an angular air shield at the top of its open end.
 5. The structure of claim 3, in which the portion of said curtain material extending under said baffle, is received on a collapsible metal shaft, designed to prevent spontaneous combustion which is positioned with respect to said booth, that it may be removed and unloaded from the rear of said booth and outside of the work area.
 6. The structure of claim 5, in which the said curtain mateRial is reinforced with a scrim layer of woven fabric material. 